Originally Posted by
maddog34
Please quit trying to stretch every response into a lengthy discussion, and adding pointed false assumptions. Thanks.
the rings shown by Kmeyer93 appear to be identical to the nearly un-used ones i have here, except for obvious wear on many of K's rings' teeth... which isn't super-bad wear, but still quite obvious, if you know what to look for. PS.. that wear varies from tooth to tooth, making it not as obvious to untrained eyes.
Please quite trying to cast aspersions. Mine is
not an untrained eye.
look closely.. you'll see that the rings bolt up at a very small BCD.. just like the early Shimano MTB alivio crankset i have in stock.
those alivio cranksets had a Decal on the outer face of the arms that got wiped off most of them by shoe rub.
there is no Shimano parts Code on the back of the arms.
You extrapolating a whole lot from a couple of very close pictures. There is no picture of the outer face of the crank so how can you tell if the crank is an Alivio or some other generic crank. There is no picture of the crank arm from which to tell if there is a code or not.
But all that means nothing. You said
Originally Posted by
maddog34
those are "clean out grooves" designed to evacuate built up gritty chain grunge, etc.
the fact that they are now turning into yawning cracks, and that the teeth adjacent to them are in a different plane, is not good... i don't care if "they were designed that way".. not good.
They aren’t “yawning cracks” and are nothing to worry about.
the mid and big ring have a few "W Cut" teeth, meaning they a tiny bit shorter, and are flat on top, until they wear some after a few thousand shifts....
the W Cut teeth are not adjacent to the cheap stamped shift "pins".
Not in the pictures I’ve seen. The teeth look pretty much the same size all the way around. Compare the teeth to the photos of chainrings I posted.
obvious conclusion: i have the un-worn version here to look at now, from any angle i choose.
Ideally, the worn rings should be replaced, but are not critical at this time.
that BCD has never been covered by the aftermarket in this century, and Sheldon never recorded that BCD.
When Replacement is Needed, just Install a newer design crankset, with more modern, better shifting.
break's over.. back to work on a fairly well preserved K2 ZED MTB.
Brown did record the BCD
Granted, the chainring has a really weird BCD that is a dead end. But there is no need to replace anything…nor worry about a problem that doesn’t exist. Those are steel rings that are barely worn and don’t need to be replaced anytime soon. Those rings probably won’t need to be replaced for decades of hard use with just a modicum of care.
My objection here is the advice you are giving that this feature is a problem and needs to be addressed. It isn’t and doesn’t.